Offshore tanker loading and unloading apparatus



Jan. 21, 1964 1 slEGEL 3,118,155

OFFSHORE TANKER LOADING AND UNLOADING APPARATUS Filed July l2, 1961 5 Sheets-Sheet 1 J. slEGEL 3,1135155 OFFSHORE TANKER LOADING ANO UNLOADING APPARATUS Jan. 21, 1964 5 Sheets-Sheet 2 INVENTOR L/Tvf//fga BY Filed July 12, 1961 ATTO RNEY Jan. 21, 1964 J. SIEGEL 3,118,155

OFFSHORE TANKER LOADING AND UNLOADING APPARATUS Filed July l2, 1961 5 Sheets-Sheet 3 |||I- n, 11| W H1. M n. rlI n.1

Jan. 21, 1964 J. slEGr-:L 3,118,155

OFFSHORE TANKER LOADING AND UNLoADNG APPARATUS Filed July l2, 1961 5 Sheets-Sheet 4 BYL..

Jan. 21, 1964 J. slEGEL 3,118,155

OFFSHORE TANKER LOADING AND UNLOADING APPARATUS A Filed July 12, l1961 5 sheets-sheet 5 H Il 59 dg; y n I U n" l KM i i u 1li-. P1 L11 IVW u! (87 37 90 Z7 2/ (87 8 7 EL 2 a ATTO R N EY United States Patent O 3,iis,is5 GFFSHGRE TANKER LABlNG AND UNLOADING APPARATUS .loseph Siegel, 5 Glen lane, Port Washington, N.Y. Filed July 12, i961, Ser. No. 123,490 4 Claims. (Ci. 9 8) The present invention relates to improvements in olfshore loading and unloadint7 apparatus for tankers carr ing oil and other liquid products.

ln the loading and unloading of oil tankers, and particularly in the case of large of supertankers, situations exist at many points in which it is necessary to moor the vessel oishore 'throughout the transferring operation. Under such circumstances it is common practice to employ a flexible hose normally lying on the seat bottom, its inner end being connected to the submarine pipe line or" the shore installation and its outer end being provided with a ma :1g buoy. To prepare for a transfer, mooring is first accomplished by utilizing a system of Xed stern and breasting mooring buoys and anchors together with the tankers own bow anchors, to locate the vessel with the manifold piping in close proximity to the seaward end of the submerged hose as indicated by the marking buoy. The hose is then raised from the sea bottorn by means of the tankers hoisting boom and attached to the ships piping system. in the raising operation a great deal o time and effort must be expended in detaching the hose buoy and associated equipment from the seau/ard end of the hose, particularly if the sea condition is other .than dead calm. Similarly, after transfer is completed undue amounts of time and effort are involved in re-attaching the hose buoy and related equipment and in returning the hose to the sea bottom free of kinks and stretched in proper position for the next raising.

ln the present trend of construction and use oi larger and operationally more economical tankers or supertankers, to to speed up transfer and minimize demurrage costs the use or" a plurality of large submarine hoses is indicated in order to utilize the tankers extremely large pumping capacity during unloading, or in the case of loading, to cut the filling time to a minimum. However, the use of such multiple hoses by the above described established practice has proved impractical due to several factors. in the iirst place, the hoses have tended to become entangled with one another on the sea bottom, requiring the services of a diver to straighten them before they may be raised again to the sea surface without resulting in kinked hose. Also, the previously noted expenditure of tune and effort required for detaching and reattaching the hose buoy and related equipment is obviously multiplied. On the other hand, the use of very large hoses in order to minimize their number is confronted with limitation in the tankers boom hoisting capacity as well as the possible commercial unavailability of such. oversize hoses in general manufacturing standards. ln view of the above and related difficulties, an object of the present inventionis to provide improved transfer apparatus in which the necessity for raising and lowering or the submarine hoses and detachment and reattachrnent of marking buoys is elininated.

A further object is to provide improved transfer apparatus adapted to employ any required number of standice ard hoses without any tendency toward tangling or kinking.

A further object is to provide improved transfer apparatus including a buoyant vessel or pontoon adapted to he located alongside the tanker or supertanker and constituting an intermediate connecting station between the shore installation and the tankers piping system.

A further object is to provide an intermediate transfer pontoon having piping means normally connected to one or more of the submarine hoses of a shore installation, and carrying flexible hose means located above Water at all times and adapted to complete the fluid connection between the shore installation and a tankers piping sys- A further object is to provide an intermediate transfer connecting pontoon including means to increase and decrease the draft of the pontoon in accordance with changes in the tankers draft during loading and unloading.

A further object is to provide an intermediate transfer connecting pontoon adapted to move in synchronism with the tankers or supertankers normal drift, rise and fall due to tide and swells, thus preventing undue stress on the ilexible transfer hose and its connections.

further object is to provide improved iiuid transfer apparatus adapted to effect eiiicient and economical loading of a tanker or supertanker of any given size and pumpcapacity by selective or combinational use of a plurality of hoses carried by a common intermediate connecting pontoon.

A further object is to provide improved offshore liuid transfer apparatus including a floatirig intermediate connecting station vadapted -to be ballasted to maximum submergence when not in use, thereby reducing to a minimum the amount of its surface exposed to high Winds and waves during inclement weather.

Another object is to provide odshore transfer apparatus including means for launching and receiving niultiproduct dividers in a submarine pipeline installation.

Another object is to provide offshore transfer apparatus including means for purging submarine pipe lines.

A further object is to provide an offshore station including a connecting pontoon structure movable upward and downward on guide piles secured in the ocean bottorn.

Other objects and advantages of the invention will become evident during the course of the following description in connection with the accompanying drawings, in which FIGURE l is a diagrammatic plan view of a tanker positioned for loading or unloading by apparatus in accordance with one embodiment of the invention;

FIGURE 2 is a lateral View illustrating the relationship of the tanker and the connecting pontoon structure as shown in FIG. 1 when both are in their positions of maximum submergence;

FlGURE 3 is a view similar to FIG. 2 showing the tanker and pontoon in their positions of minimum draft;

FIGURE 4 is an exterior end view of the connecting pontoon structure;

FIGURE 5 is a longitudinal view of the structure of FG. 4, partly in section, and illustrating typical arrangements ofthe piping and hose equipment;

FIGURE 6 is a top view of the structure shown in FIG. 5;

' Sil to wht FIGURE 7 is a diagrammatic illustration of the ballast pump connections;

FlGURE 8 is a horizontal sectional view of the pontoon structure in the plane 8 8, FIG. 5;

FIGURE 9 illustrates an island type loading and unloading station in accordance with the invention;

FIGURE l() illustrates in plan view the guiding system for the connecting pontoon structure, shown in FIG. 9, and

Fl-GURF. 11 is a rear or offshore directed view of the embodiment of the invention shown in FIGS. 9 and l0.

Referring to FG. l, the numeral designates a tanker moored off the shore 21 on which is situated a petroleum supply or receiving installation such as a tank farm or the like, the seaside piping system of the onshore plant being generally indicated at 22. The tanker is moored by means of a system of permanently located stern and breasting mooring buoys 23 and anchors 24 in combination with the ships bow anchors 2:5, the moored position being such as to place the tankers loading and unloading piping facilities 26 in close juxtaposition with a hose buoy or intermediate connecting pontoon station 27. Underwater pipes 2S, 29, and 3h run offshore along the ocean bottom to a point 31 conveniently marked by a spar buoy 32, whence they are connected respectively by ilexible hoses 33, 34, and 35 to the lloating station 27 in the manner illustrated in FIGS. 2. and 3. Referring to Vthese latter figures, it will be seen that the underwater flexible hoses are connected to risers extending upward through the bottom of the floating intermediate station unit 27, the individual connecting arrangements of all the submarine lines being typified by the connection of the hose 33 from the submarine pipe 23 at point or zone 31 to the corresponding riser 36.

The construction and equipment of the station unit 27 shown in detail in FIGS. 4, 5, 6, 7, and 8, are as follows.' The hull or buoyancy element is a pontoon 37 having a Water-tight top closure plate 3S (see FIG. 5), above which is disposed a top operating deck 3?. The pontoon 33 is constructed with a plurality of transverse bulkheads 46 dividing it, in the present example, into live compartments 4l, dla, filb, d10 and 41d. A system of vent pipes 42, terminating in upper goose-necks 43, affords t open connections from the various compartmentsto the atmosphere, and the bulkheads 40 are provided with lower openings 43 to permit equalization or the ballast water level in the compartments. The riser pipes 36, 44 and 45, connected respectively to the submarine hoses 33, 34 and 35, extend upward through the bottom of the pontoon, t e top plate 3d and the deck 39. The riser pipe 35, which in the present example is of substantially larger diameter than the other two, terminates in an upper header 46 secured in saddles 47 mounted the deck 39.

t Three vertical loading arm pipes 48, equipped with gate valves 49, extend upward from the header 46 and are surmounted by angular swivel fittings Sil to which are with the usual manual operating handles or wheels 52 as shown in FEGS. 2, 3 and 4, but that the `detail showing of such handles is omitted from the diagrammatic representation of the valves in the other ligures in order to avoid unnecessary complication in illustration.

The riser pipes 44 and l5 continue directly upward as individual loading arm pipes 53 and 34, equipped with valves 5S and if; respectively and topped by swivel fittings n are attached final connecting hoses 57 and 58. A horizontal cross-over pipe 53, provided with a valve 6G, is adapted to eiifect 'a transfer connection between the loading arms 53 and 54 when desired. Also connected into the arm 53 is a valved lock structure 6l, FIG. 8, for use in launching and receiving multi-product pipeline dividers.

A ballast pumping assembly 6E is mounted on the deck 39 as shown in plan in FlG. 6. ribis assembly, which is adapted to effect any desired change in the amount of ballast water contained in the pontoon 37 in order to adjust the latters degree of submergence, consists of a pump 63 provided with a driving motor 64, an alternatively suction or delivery pipe 65 extending down Within the pontoon hull, overboard suction and discharge pipes 66 and 67, and a ilow-reversing arrangement which may best be understood in connection with diagrammatic FIG. 7. Referring to FlG. 7, it Will be seen that the suction end 63 of the pump 63 has two alternative con nections, namely via a gate valve 69 with the overboard suction pipe 65 or via a second valve ll and a branch pipe 71 with the interior pipe 65. Similarly, the discharge end '72 may alternatively be connected via a valve 73 to the overboard discharge pipe 67 or via a valve 7d to the interior pipe 65. Thus by opening valves d@ and 74 while closing 73 and 73, the pump 63 will be caused to deliver Water from the ocean into the pontoon through the interior pipe 65; similarly, when valves 'itl and 73 are opened while 69 and 74- are closed, Water will be withdrawn from the pontoon through the pipe 65 and discharged overboard. It will further be evident that if desired, by adjustment of the various valves a partial bypass or feedback llow may be set up between the discharge and suction ends of the pump, thus in effect vary ing the latters pumping capacity so as to regulate the pontoons rate of submergence or emergence independently of the pumps normal speed and maximum delivery rate.

During periods when the inal connecting hoses 51,

57 and 58 are not in use their outer ends are retained tion in the event of sudden unduly high tidal Wave ino-- tion. Other exterior fittings of the pontoon 27 include a series of vertical fenders or bumpers 79 disposed on the sides and ends of the hull, a guard rail Sil around the deck 39, FIG. 6, and a boarding ladder Si. Four lugs 82, projecting from the V bottom of the pontoon hull near the outer corners thereof, are tted with shackles 33 for attachment of chains 84 leading to fixed anchors on the sea bottom 36, as shown in FGS. 2 and 3.

A typical transfer procedural operation is as follows: Assuming rst that a tanker or supertanker Ztl is to be unloaded to shore, the ship is moored with the pontoon station Z7 alongside in proper location as previously set forth in connection with FIG. l, ships lines 8S (FIG. 6) being attached to the cleats 7? as noted above. Since the tanker 29 is initially loaded, it rides low in the water as illustrated in FlG. 2. Accordingly, the pontoon hull 37 initially is heavily ballasted with Sea Water by means of the pumping assembly 62 so as also to lie low in the Water as shown. The final connecting hoses Si, etc., are detached from their supporting spuds 76, hoisted and attached to the tankers piping system. Whether all the hoses 5l, etc., or only part of them are so used is determined by the number required to utilize to best advantage the maximum pumping capacity and to match the piping system of the particular supertanker or smaller vessel to be unloaded. The hose connections having been completed, the corresponding valves 49 are opened and the tankers cargo is pumped downward through the pontoon stations previously described internal piping to the permanently connected submarine hose and piping system and thence to the shore establishment 22. As the unloading progresses the ballast water in the pontoon 37 is reduced by means of the pumping assembly 62, increasing the effective buoyancy of the entire intermediate connecting unit 27 so that it rises in concert with the increased emergence of the tanker until the latters final unloaded situation is reached as illustrated in FIG. 3. The upward movement of the unit 27, together with the yielding swing of the swivels 50, reduces the necessary fiexing of the final connecting hoses to a minimum, increasing durability and permitting the hose units to be of relatively short length and consequent light weight.

It will be noted that during the foregoing operation the upward liexing of the submarine hoses 33, etc., is accomplished by the buoyancy of the pontoon 37 rather than by any direct connection with the tankers equipment. Thus the interposition of the pontoon station 27 relieves the final connections to the tanker of all stress except that necessary to support the relatively light hoses 51 and their fluid content. Similarly, the ships boom hoisting equipment in effecting the initial pumping connections is required only to hoist the ends of the hoses 51 from the deck level of the pontoon station 27, irrespective of how large, heavy or numerous the submarine hoses may be. In the latter respect, the provision of the header or manifold 46 on the pontoon station, FG. 5, permits the submarine hose 33 connected thereto to be of a large size which in prior practice would be beyond the hoisting capacity of the tankers equipment, but which latter equipment in the present invention has only to deal with the smaller standard those sections 51, as noted. Ihe optional use of larger submarine hoses and pipes in turn allows them to be fewer in number to provide a given maximum transfer capacity, thus reducing both initial and maintenance costs, while at the same time the diversification of final connections provided by the intermediate pontoon station renders the system flexibly adapted to serve all sizes of tankers with maximum eiiiciency. The factor of efficiency obviously includes the ease and quickness of connecting the hoses 51 to the tankers piping system Z and their final disconnection at the completion of transfer, both of which operations are conducted entirely above water, eliminating the hitherto laborious and time consuming necessity for dragging up separate submarine hoses, disconnecting them from buoys and subsequently re-connecting them thereto. The fact that except for long-term repairs or replacements, the submarine hoses remain attached to the pontoon station 27 and at all times prevent any tangling or kinking of these hoses.

The procedure in loading a tanker from shore generally parallels that described for unloading, except that the initial positions of the tanker and pontoon station 27 are as shown in FIG. 3, the pontoon station thereafter being ballasted to greater submergence by means of the pumping equipment 62 as the loading progresses to the final relation shown in FiG. 2. Current supply for the motor 64 of the pumping equipment may be derived either from the tankers electric system or via suitable waterproof cable from the shore station, the latter arrangement being generally preferred as it renders the motor operation independent of possible voltage or other differences in available current supply from various tankers, as well as permitting operation in the absence of any tanker. If found desirable in certain station locations, the motor 6e? may be replaced by a suitable internal combustion engine, thus rendering the ballast pumping system a completely self-contained unit.

ln addition to the described advantages of the invention in effecting loading and unloading operations, the interposition of the pontoon station 27 allows the provision of means to carry out transfer and maintenance operations hitherto not feasible in conventional offshore installations. For example the valved lock structure 6l, FlG. 6, permits the introduction and reception of multiproduct dividers at the extreme outer end of the transfer system, with advantages obvious to those skilled in the art. Similarly, valved cross connections such as 59-613, FIG. 5, provide for ready transfer of fluid from one pipe 'line to another, and in combination with the shore stations pumping apparatus, facilitate the purging of the pipe lines, including the submarine hose and piping portions, of obstructions such as heavy wax accumulations.

In the island type of loading and unloading station shown in FIG. 9 the tanker 20 is tied up to a series of permanent offshore mooring platforms 87, the latter being built up from the ocean bottom to a level above mean high tide. Adjacent platforms at the ends of the series are provided with bridges 88 to facilitate the mooring and cast-off operations. With this type of installation the floating intermediate or pontoon station 27 may be located by the alternative means illustrated in FIGS. l() and ll instead of by chains and anchors as in FIGS. 2 and 3. The locating and guiding means in this case consists of a suitable pattern of piles 89, preferably of H-beam section, which have been driven and rigidly fixed in the ocean bottom 35. Runners 9i?, secured -to the pontoon 37, loosely engage the piles 89 in vertical guiding relation, so that the pontoon station is free to rise and lfall in response to tidal changes and changes in its own ballast condition as previously described. It will be understood that the deck equipment, piping, underwater hose connections, and mode of operation of the intermediate connecting station 27 are the same as those previously explained and therefore need not be further described herein.

In both types of locating arrangement of the pontoon station, the latter may be ballasted to maximum submergence during periods between transfer operations, thus presenting minimum upper area to winds and wave action in case of inclement weather; this is obviously an addition to the normal operational advantages of the ballast pumping equipment 62.

In the foregoing description the pontoon station 27, which provides efficient shipside procedures hitherto not attainable in offshore yloading and unloading operations, the station has been shown with three submarine connecting lines and five above-water final connecting lines, three of the latter being branched from the header da. It will be obvious, however, that the pontoon station may be built with any other desired piping and hose combination called for by particular shore station situation and range of tankers to be served, the same applying to the number and arrangement of cross-over connections or manifolds exemplied by 59-60, FIG. 5, as well as to the facility provided by the deck 39 for the mounting of such auxiliary equipment as meters, gauges, and the like at substantially the immediate point of transfer. Thus, while the invention has been described in preferred form, it is not limited to the precise embodiments illustrated, as various modifications may be made without departing from the inventive concept within the scope of the appended claims.

What is claimed is:

1. In apparatus for transfer of fluid between a marine tanker moored at a predetermined offshore location and a shore station having submarine piping directed toward said offshore location, in combination, an intermediate connecting station retained offshore in close prom'mity to said tanker location including a hull with a vertical side structure adapted to operationally abut a side of said tanker in vertically and horizontally guided relation throughout a substantial area of said tanker side and further including a piping system secured to said hull, means to raise and lower said intermediate station in operative concert with changes in draft of said tanker, means to secure said hull to said tanker side in said abutted guided relation, yieldable submarine transfer means connecting said submarine piping to said piping system of said intermediate station, and liexible hose means carried above water by said intermediate station and adapted to be attached to the piping system of said Itanker for connecting the same to said piping system of said intermediate station, where- 7 by uid transfer communication may be completed between said tanker and shore establishment through said intermediate station.

2. Apparatus according to claim 1 wherein said hull comprises a structure having essentially vertical side walls, a bottom Wall and a top Wall, and a top deck spaced above said top wall, the space between said top wall and deck being open to permit the free flow of water therethrough when the top wall is approximately at or below the water surface.

3. Apparatus accordi-ng to claim 2 wherein said bottom wall is of V-shaped section.

4. Apparatus according to claim 2 wherein said hull includes internal partitions and said means of raise and Klower said station comprises a selectively controlled pump 15 for pumping Water into and out of said hull.

References Cited in the tile of this patent UNITED STATES PATENTS FOREIGN PATENTS Great Britain Apr.

Australia Feb 

1. IN APPARATUS FOR TRANSFER OF FLUID BETWEEN A MARINE TANKER MOORED AT A PREDETERMINED OFFSHORE LOCATION AND A SHORE STATION HAVING SUBMARINE PIPING DIRECTED TOWARD SAID OFFSHORE LOCATION, IN COMBINATION, AN INTERMEDIATE CONNECTING STATION RETAINED OFFSHORE IN CLOSE PROXIMITY TO SAID TANKER LOCATION INCLUDING A HULL WITH A VERTICAL SIDE STRUCTURE ADAPTED TO OPERATIONALLY ABUT A SIDE OF SAID TANKER IN VERTICALLY AND HORIZONTALLY GUIDED RELATION THROUGHOUT A SUBSTANTIAL AREA OF SAID TANKER SIDE AND FURTHER INCLUDING A PIPING SYSTEM SECURED TO SAID HULL, MEANS TO RAISE AND LOWER SAID INTERMEDIATE STATION IN OPERATIVE CONCERT WITH CHANGES IN DRAFT OF SAID TANKER, MEANS TO SECURE SAID HULL TO SAID TANKER SIDE IN SAID ABUTTED GUIDED RELATION, YIELDABLE SUBMARINE TRANSFER MEANS CONNECTING SAID SUBMARINE PIPING TO SAID PIPING SYSTEM OF SAID INTERMEDIATE STATION, AND FLEXIBLE HOSE MEANS CARRIED ABOVE WATER BY SAID INTERMEDIATE STATION AND ADAPTED TO BE ATTACHED TO THE PIPING SYSTEM OF SAID TANKER FOR CONNECTING THE SAME TO SAID PIPING SYSTEM OF SAID INTERMEDIATE STATION, WHEREBY FLUID TRANSFER COMMUNICATION MAY BE COMPLETED BETWEEN SAID TANKER AND SHORE ESTABLISHMENT THROUGH SAID INTERMEDIATE STATION. 